Thanks for the kind replies. i'm a little bit flexible on the budget for the right solution. will look into all the recommendations made here.
i had ruled out foscam because of the inability to have a centralized recording system unless you use their cloud in which case there's a monthly charge.
I'm happy to buy a product from china if it is good and is recommended here. I will be installing the cameras in Singapore (which i missed saying in my original post as i wasn't sure it was relevant).